<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../react18/react.development.js"></script>
    <script src="../react18/react-dom.development.js"></script>
    <script src="../react18/babel.min.js"></script>
    <script src="../react18/prop-types.js"></script>
</head>
<body>
    <div id="app"></div>
    <script type="text/babel">
    /* 
      如果发生事件的时候,需要获取自身元素的时候,可以直接使用e.target

    */
   class Parent extends React.Component{
        iptEle =React.createRef();
        render(){
            return(
                <div>
                    <input tpype="text" ref={this.iptEle}/>
                    <button onClick={this.handle}>点我弹出用户的输入内</button>
                
                    <input type="text" onChange={this.iptChangeHandle} placeholder="表单修改后弹出输入的内容" />
                </div>
            )
        }
        handle=()=>{
            console.log(this);
            const {value} =this.iptEle.current;
            alert(value)
        }
    // 这个是输入完后失去焦点，然后弹出输入的内容
        iptChangeHandle = (e) =>{
            console.log(e.target.value);
        }
   
    }
    const root =ReactDOM.createRoot(document.getElementById('app'));
    root.render(<Parent/>)
    </script>
</body>
</html>